1. Field of the Invention
The present invention relates to a liquid jet head and an actuator apparatus provided with a lower electrode, a piezoelectric layer, and an upper electrode.
2. Description of Related Art
A piezoelectric element used for a liquid jet head or the like is an element provided with a piezoelectric film formed of a piezoelectric material having a function of electrical-mechanical conversion between two electrodes, and the piezoelectric film is formed of, for example, crystallized piezoelectric ceramics.
As a liquid jet head using such a piezoelectric element, for example, there is an ink jet printing head in which a part of a pressure generating chamber communicating with nozzle openings for ejecting ink droplets is formed of a vibration plate, and the vibration plate is deformed by a piezoelectric element to pressurize ink in the pressure generating chamber, thereby ejecting the ink droplets from the nozzle openings. Two kinds of ink jet printing heads has been put to practical use, one uses a vertical vibration mode actuator extending and contracting in the axial direction of a piezoelectric element, and the other uses a deflection vibration mode actuator. In such actuators, a piezoelectric element capable of obtaining a large deflection with a low driving voltage to dispose the actuators with high precision, that is, a piezoelectric element having large displacement is required.
To improve the displacement characteristics of the piezoelectric layer, the diffraction peak position of X-lay of the piezoelectric layer is restricted, for example, as described in JP-A-2006-278835.
However, even when the piezoelectric element is provided using a ferroelectric film, satisfactory displacement cannot be obtained. Such a problem is not limited to a liquid jet head represented by an ink jet printing head, and the problem also applies to another actuator in the same manner.